1. Field of the Invention
The present invention relates to the field of telephone call processing systems. Specifically, the present invention relates to call processing systems with facsimile processing capability.
2. Prior Art
Telephone communication has expanded from a purely voice medium to a system supporting all types of information interchange. It has become increasingly important to be able to handle a multitude of incoming telephone lines each of which may support voice communication, facsimile transmissions, or other forms of information interchange. One well-known way of handling the multitude of incoming telephone lines is the use of a private branch exchange (PBX) or central exchange (Centrex). A PBX or Centrex is a telephone exchange system serving an organization, which may be coupled with multiple incoming and outgoing trunk lines and multiple telephone sets at the organization's premises. PBX or Centrex systems provide a variety of functions such as switching of calls from the incoming trunk lines to any of the extensions, switching calls between two extensions and switching calls between extensions and outgoing trunk lines. Numerous PBX and Centrex systems are well-known and commercially available.
Conventional call processing and voice messaging system are known in the art and are commercially available. These call processing systems may be coupled with a PBX or Centrex and used to automate the answering of incoming calls from the outside telephone network and the taking of messages when the extensions are not answered by the called parties. These prior art call processing systems include (1) automated attendant systems for directing incoming calls to an extension, (2) voice messaging systems for handling a call that does not complete connection to an extension, (3) two-way voice messaging systems or voice store and forward systems for speaking messages to a caller from fixed address mailboxes, and (4) interactive voice response systems for retrieving data from a database of information and response to a caller request and speaking messages to a caller. A telephone call processing system is described in copending patent application Ser. No. 07/660,279, entitled "Integrated Application Control Call Processing and Messaging System", filed Feb. 21, 1991.
The incorporation of facsimile capability into prior art call processing systems has proved too troubling, because facsimile transmissions and voice data cannot be transmitted on the same telephone line at the same time using the current telephone network. The tendency has been to dedicate one set of telephone lines for facsimile transmission and a different set of lines for voice data transmission. Thus, particular telephone lines with distinct telephone numbers are dedicated to the transmission of facsimile data. Although this solution is perfectly acceptable in some applications, the dedication of facsimile (fax) lines does not lend itself to a flexible system architecture.
In other prior art call processing systems, incoming telephone lines from a PBX or central office are routed into the call processing system through a series of voice ports. One voice port is provided for each incoming telephone line. For each voice port supporting only voice data communications, only a voice interface is provided in the voice port. For telephone lines supporting either voice data communications or facsimile data communications, a voice interface and a separate facsimile interface are provided within the voice port. Using an established set of commands, a caller or user may select either the voice interface or the facsimile interface for servicing a particular telephone call. In this manner, a particular telephone line may be used for both voice and facsimile data communications.
A number of problems exist with the prior art dual interface voice port architecture. First, it is necessary to predetermine which telephone lines will service facsimile data. These telephone lines must be provided with a facsimile interface. By having to predefine telephone lines that will service facsimile data, the overall flexibility of the call processing system is substantially decreased. Secondly, the cost of these prior art call processing systems is increased by having to provide facsimile interfaces for telephone lines that may not necessarily require them. Thus, these prior art call processing systems do not provide enough flexibility for allocating resources in an efficient manner.
Some prior art systems provide a capability known as fax-on-demand. Using this capability, a caller may dial into a fax-on-demand processing system and make selections from a menu of available fax information. Typically, selections are made using DTMF tones as entered on a telephone key pad. After the caller makes a selection, the fax-on-demand system transmits back to the caller the requested information by facsimile transmission means. Prior art fax on-demand systems typically employ a dual interface voice port for providing the fax on-demand service. As such, these systems suffer the same lack of flexibility in servicing both voice and facsimile data communications. Specifically, a strong distinction is made between the voice data communications and the facsimile data communications. These systems are unable to handle voice or facsimile data as a single source of information. It is, therefore, o difficult and cumbersome to move back and forth between the two transmission mediums.
Thus, a better call processing system for handling facsimile data communications is required.